Multi-frequency terahertz wave generation device based on optimized cascade difference frequency

Abstract

The invention provides a multi-frequency terahertz wave generation device based on optimized cascade difference frequency. Mixed frequency light enters a PPLN crystal, cascade light of all stages is generated through the cascade optical difference frequency effect, the cascade light of all stages passes through a sixth reflecting mirror and a seventh reflecting mirror and then enters a fan-shaped structure PPLN crystal, an included angle theta is formed between the cascade light entering the fan-shaped structure PPLN crystal and the positive direction of the X axis; terahertz waves are generated by the cascade light in the fan-shaped structure PPLN crystal through the cascade optical difference frequency effect; the terahertz waves of multiple frequencies can be obtained by changing the incident position and the incident angle of the cascade light in the fan-shaped structure PPLN crystal; the terahertz waves are coupled out through a parabolic mirror to change the incident position and the incident angle theta of the cascade light, the terahertz waves with different frequencies can be obtained, the tuning mode is simple, and operation is flexible. By changing the polarization period distribution of the an-shaped structure PPLN crystal, the Stokes cascade difference frequency can be enhanced, meanwhile, the anti-Stokes cascade difference frequency is inhibited, and the terahertz wave optical conversion efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of terahertz wave applications, and in particular relates to a multi-frequency terahertz wave generator based on optimized cascaded difference frequencies. Background technique [0002] Terahertz wave (Terahertz, referred to as THz), refers to the frequency of 0.1-10THz (1THz = 10 12 Hz) in the range of electromagnetic waves, whose band is between millimeter waves and infrared rays in the electromagnetic spectrum, which is the transition area between photonics and electronics, and macroscopic theory to microscopic theory. The special position of terahertz wave makes it widely used in basic research fields such as physics, chemistry, astronomy, molecular spectroscopy, life science and medical science, as well as medical imaging, environmental monitoring, material detection, food detection, radio astronomy, mobile communication, satellite Applied research fields such as communication and military radar have ...

AI Technical Summary

Problems solved by technology

[0014] The purpose of the present invention is to provide a multi-frequency terahertz wave generating device based on optimized cascaded difference frequency to solve the problems of equipment complexity for outputting terahertz waves of different frequencies

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